Atlanta , Georgia -LRB- CNN -RRB- -- The FBI is asking for public assistance in finding a serial bank robber dubbed the `` Granddad Bandit , '' who is believed to have struck in at least seven states .

The man , thought by authorities to be between 50 and 60 years old , is suspected in a string of nine bank robberies beginning in April in Houston , Texas , the FBI 's Atlanta Field Office said in a news release .

Since then , police believe he has robbed two banks in Atlanta and single banks in Roanoke , Virginia ; Little Rock , Arkansas ; Dallas , Texas ; Birmingham , Alabama ; Syracuse , New York ; and Tallahassee , Florida , the last bank robbery , which occurred on October 16 .

`` His robberies are described as being calm , with a deliberate attempt to not attract attention to himself , '' the FBI said . `` The robber quietly presents a demand note to the victim teller and thereafter departs the bank without disruption to normal banking business going on around him . ''

The man is described as being between 6 feet and 6 feet 4 inches tall and weighing between 220 and 250 pounds . He is described as stocky and bald , with short gray hair on the sides , and wears glasses .

A $ 10,000 reward is being offered by law enforcement . To offer information in the case , contact the Atlanta FBI .

In September , a man sought in at least 10 bank robberies in at least four states was arrested in Missouri . The FBI posted photos from the bank robberies on billboards , leading to the man identified as Chad Schaffner . A retired state trooper saw Schaffner in Kingdom City , Missouri , and notified authorities .

Schaffner is suspected of robbing banks in states including Kentucky , North Carolina , South Carolina and Tennessee , authorities said .

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Last bank robbery occurred October 16 in Tallahassee , Florida

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FBI : `` His robberies are described as being calm , with a deliberate attempt to not attract attention ''

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He is described as stocky and bald , with short gray hair on the sides , and wears glasses